Tap water to blame for salmonella outbreak?

March 21, 2008 4:55:24 AM PDT

DENVER, CO --

The number of confirmed salmonella cases rose in a southern Colorado city on Thursday, as health officials investigated whether the outbreak was caused by tainted tap water. Alamosa spokeswoman Connie Ricci said there were 47 confirmed cases of salmonella among city residents, up from 33 a day before. She said 76 other cases were under investigation.

Health officials said the tap water in Alamosa, a community of 8,500 about 160 miles south of Denver, tested positive for bacteria that are believed to be salmonella, but they were still awaiting final test results for confirmation. The cause of the contamination was under investigation.

Health officials have warned residents to boil tap water for 15 seconds to kill the bacteria, or use bottled water for brushing teeth, washing dishes, making ice, cooking, drinking and making baby formula. They said people can use tap water to bathe, as long as they are careful not to ingest it.

City and county officials set up four centers where residents could get free bottled water or bring containers to fill with safe water, Ricci said. Residents were limited to one gallon of free water per person per day.

State emergency management officials activated an emergency operations center in the Denver suburb of Centennial to help coordinate deliveries of bottled water.

Timothy Rivera, the manager of Mrs. Rivera's Kitchen in a downtown Alamosa, said the restaurant stayed closed Thursday because of the outbreak.

"It takes a lot of manpower for all this stuff. We have to boil water for everything, to wash dishes," he said. "We have to have bottled water, we have to have ice. There's lots of things to take into consideration."

He said he hoped to reopen Friday.

Waterborne salmonella outbreaks are fairly rare, said Mark Salley, a spokesman for the Colorado Department of Public Health and Environment. The bacteria are typically spread by food, he said.

Salmonella can cause diarrhea, fever and stomach pain. Victims typically recover on their own, but the elderly, infants and people with impaired immune systems may require treatment. Untreated, salmonella can cause death in vulnerable victims, the health department said.

City officials plan to start flushing and disinfecting the water system in the next few days, a process that could take a week or more. While the flush is under way, no municipal water should be used, even if it is boiled, they said.

Authorities said the first salmonella victim began showing symptoms around March 8, and state health officials became aware of the outbreak Friday.

Officials tested city water on Monday, and the results showing bacteria in the water system came back Wednesday.